I don't think realizing can have a direct object in this way.
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Barrie EnglandOct 21 '13 at 6:14

Yes – though the standard dictionary definition of the intended sense doesn't inform the reader of this restriction on what the DO can be: realize - be fully aware or cognizant of (WordNet 3.0). realize the importance of the increase in numbersbut not (in this sense) realize the increase in numbers–notice the increase in numbers works.
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Edwin AshworthOct 21 '13 at 9:16